/**
 *
 * \section COPYRIGHT
 *
 * Copyright 2013-2020 Software Radio Systems Limited
 *
 * By using this file, you agree to the terms and conditions set
 * forth in the LICENSE file which can be found at the top level of
 * the distribution.
 *
 */

/**********************************************************************************************
 *  File:         chest_ul.h
 *
 *  Description:  3GPP LTE Uplink channel estimator and equalizer.
 *                Estimates the channel in the resource elements transmitting references and
 *                interpolates for the rest of the resource grid.
 *                The equalizer uses the channel estimates to produce an estimation of the
 *                transmitted symbol.
 *
 *  Reference:
 *********************************************************************************************/

#ifndef SRSLTE_CHEST_UL_H
#define SRSLTE_CHEST_UL_H

#include <stdio.h>

#include "srslte/config.h"

#include "srslte/phy/ch_estimation/chest_common.h"
#include "srslte/phy/ch_estimation/refsignal_ul.h"
#include "srslte/phy/common/phy_common.h"
#include "srslte/phy/phch/pucch_cfg.h"
#include "srslte/phy/phch/pusch_cfg.h"
#include "srslte/phy/resampling/interp.h"

typedef struct SRSLTE_API {
  cf_t*    ce;
  uint32_t nof_re;
  float    noise_estimate;
  float    noise_estimate_dbm;
  float    snr;
  float    snr_db;
  float    cfo;
  float    ta_us;
} srslte_chest_ul_res_t;

typedef struct {
  srslte_cell_t cell;

  srslte_refsignal_ul_t             dmrs_signal;
  srslte_refsignal_ul_dmrs_pregen_t dmrs_pregen;
  bool                              dmrs_signal_configured;

  srslte_refsignal_srs_pregen_t srs_pregen;
  bool                          srs_signal_configured;

  cf_t* pilot_estimates;
  cf_t* pilot_estimates_tmp[4];
  cf_t* pilot_recv_signal;
  cf_t* pilot_known_signal;
  cf_t* tmp_noise;

#ifdef FREQ_SEL_SNR
  float snr_vector[12000];
  float pilot_power[12000];
#endif
  uint32_t smooth_filter_len;
  float    smooth_filter[SRSLTE_CHEST_MAX_SMOOTH_FIL_LEN];

  srslte_interp_linsrslte_vec_t srslte_interp_linvec;

} srslte_chest_ul_t;

SRSLTE_API int srslte_chest_ul_init(srslte_chest_ul_t* q, uint32_t max_prb);

SRSLTE_API void srslte_chest_ul_free(srslte_chest_ul_t* q);

SRSLTE_API int srslte_chest_ul_res_init(srslte_chest_ul_res_t* q, uint32_t max_prb);

SRSLTE_API void srslte_chest_ul_res_set_identity(srslte_chest_ul_res_t* q);

SRSLTE_API void srslte_chest_ul_res_free(srslte_chest_ul_res_t* q);

SRSLTE_API int srslte_chest_ul_set_cell(srslte_chest_ul_t* q, srslte_cell_t cell);

SRSLTE_API void srslte_chest_ul_pregen(srslte_chest_ul_t*                 q,
                                       srslte_refsignal_dmrs_pusch_cfg_t* cfg,
                                       srslte_refsignal_srs_cfg_t*        srs_cfg);

SRSLTE_API int srslte_chest_ul_estimate_pusch(srslte_chest_ul_t*     q,
                                              srslte_ul_sf_cfg_t*    sf,
                                              srslte_pusch_cfg_t*    cfg,
                                              cf_t*                  input,
                                              srslte_chest_ul_res_t* res);

SRSLTE_API int srslte_chest_ul_estimate_pucch(srslte_chest_ul_t*     q,
                                              srslte_ul_sf_cfg_t*    sf,
                                              srslte_pucch_cfg_t*    cfg,
                                              cf_t*                  input,
                                              srslte_chest_ul_res_t* res);

SRSLTE_API int srslte_chest_ul_estimate_srs(srslte_chest_ul_t*                 q,
                                            srslte_ul_sf_cfg_t*                sf,
                                            srslte_refsignal_srs_cfg_t*        cfg,
                                            srslte_refsignal_dmrs_pusch_cfg_t* pusch_cfg,
                                            cf_t*                              input,
                                            srslte_chest_ul_res_t*             res);

#endif // SRSLTE_CHEST_UL_H